As headsets which are worn on users' heads, conventionally there have been various forms of headsets put into practical use. For example, there is a headset having the shape shown in FIG. 1. This headset shown in FIG. 1 is constructed such that a driver unit which outputs a sound according to a provided sound signal is incorporated in both a left housing 1 and a right housing 2, and both the housings 1 and 2 are connected by a band 3 to form headphones. When a user puts on this headset, the housings 1 and 2 are each worn on the user's left and right auricles by hooking auricle holding portions 3a and 3b of the band 3, which are in the vicinity of portions connected to the housings 1 and 2, to be attached to his/her upper auricles.
Hereupon, an arm 4 is attached to the outside of the left housing 1 by means of a supporting member 5 capable of turning freely, and a microphone 6 is attached to the end of the arm 4. With this construction, when this headset is worn and connected to communication equipment such as a mobile-phone unit, sound received by the communication equipment is output from the left and right housings 1 and 2 and sound picked up by the microphone 6 is transmitted from the communication equipment, so that audio transmission and the like can be executed.
Then, the above conventional headset has a construction in which a microphone is added to headphones, and can also be used as headphones. That is, without using the microphone the headset can be used as headphones equipped with speakers. However, there has been a problem in which while the headset is being used as headphones, the microphone is unnecessary and disturbing to the user. In the case of the headset shown in FIG. 1, for example, the arm 4 to which the microphone 6 is attached can freely turn by means of the supporting member 5. Therefore, when the microphone is not being used, it is likely that the arm 4 to which the microphone 6 is attached will be turned and lifted upward as shown in FIG. 2, for example.
Although the microphone will be away from the wearer's mouth by the lift of the microphone, the microphone still remains extending from the housing 1 and stays in a position unpleasant for the wearer, which is a problem. In order to solve this problem, it is assumed that, for example, a headset has a construction in which an arm, to which a microphone is attached, can be detachable from a housing; however, in that case detaching and attaching the detachable arm takes time and effort, and also requires the user's care not to lose the microphone detached from the housing, so that there occurs a problem in which time and effort is required in handling.